1. Field of the Invention
The present invention relates to an image processing apparatus and an image processing method.
2. Description of the Related Art
When page description language (PDL) data described in a page description language is printed, an example of conventional color printers analyzes the PDL, draws a multi-valued band image on a memory, performs color conversion processing and gradation processing on the drawn band image, and prints the image after the gradation processing. Translucency drawing processing, which is not included in the conventional PDLs, is newly added to a portable document format (PDF) and an extensible markup language (XPS), which are one of the PDLs. The translucency drawing processing, in which translucent images are overlapped, is performed in accordance with set processing parameters (translucency values). Specifically, the processing parameters are generally set for respective drawing objects in such a manner that each of the images to be overlapped with each other has a translucency value equal to or smaller than one and the total of the translucency values of the overlapped image is one.
For example, Japanese Unexamined Patent Application Publication No. H7-28986 discloses the following technique. When a pixel value after synthesis of a front image and a background image is calculated, a pixel value of the background image is set to the pixel value after the synthesis in the case where the pixel value of the front image indicates transparent (translucency value=zero) or translucent (translucency value=one) for the purpose of reducing a data transfer amount and a load in computing.
The technique disclosed in Japanese Unexamined Patent Application Publication No. H7-28986, however, has a problem in that it is difficult to achieve high-speed drawing processing because the processing is performed pixel by pixel.